Gene therapy may cause leukemia
Gene therapy treats genetic diseases of the immune system, and has successfully treated patients. They were infused with immune cells that contained the correct form of the defective gene through agents called retroviral vectors. But later on, some of the patients developed leukemia, which slowed the advancement of gene therapy. Studies have been done to determine the underlying cause of leukemia, and whether other gene therapy treatments are risky. A new study revealed that early precursors of immune cells with the gene HOXB4 using the agent gammaretroviral vector became leukemic in two out of two dogs and one out of two macaques.
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